Languages are given in capital and lower-case letters; language groups, in all capitals. Languages and language groups preceded by a dagger are extinct. The number of extant languages in each genetic group is given in brackets following the name of the group. Languages preceded by an asterisk are discussed by Merritt Ruhlen in volume 2, Language Data, of his work A Guide to the World's Languages (Stanford, forthcoming.)
Reprinted from A Guide to the World's Languages, vol. 1: Classification, by Merritt Ruhlen, with the permission of the publishers, Stanford University Press. Copyright 1987, 1991 by the Board of Trustees of the Leland Stanford Junior University.
From I. J. Gelb, A Study of Writing (Chicago: University of Chicago Press, 169), pp. x-xi.